Rotating media memory devices, such as hard disk drives (HDDs) or optical disk drives (ODDs), have high data density and high speed data storage and retrieval. However, rotating media memory devices may be inadequate to meet increased data density needs of the future. For example, while the physical limit of the data density in a HDD is about 100 Gigabits (Gbits)/cm.sup.2, reliable reading and writing of data is presently constrained to data densities of approximately 10 Gbits/cm.sup.2. The physical limit of data density of an ODD is constrained by the wavelength of light used and is presently less than 1 Gbits/cm.sup.2.
Scanning memory devices proposed by Suriwa (Japanese Patent Laid-Open No. 4-289580 and U.S. Pat. No. 5,216,631) and by Saito et al. (Japanese Patent Application No. 6-270297) use the principle underlying a scanning probe microscope to read and write data to achieve data densities and data transfer rates exceeding those of HDDs and ODDs. Unfortunately, as data density and data transfer rates increase, there is a corresponding increase in errors caused by defects in storage media and in errors in data reading and writing.